The tube test is a commonly used behavioral assay to help determine the dominance ranks of mice or rats kept in the laboratory. Briefly, a narrow tube is placed horizontally on a table and cage-mates are placed at opposite ends of the tube. The cage-mates will meet in the middle and the animal that pushes the other out is considered the “winner” of that trial. All cage-mates compete with one another multiple times in a round-robin tournament to determine who is alpha, beta, gamma, epsilon, etc. More details on the protocol can be found from the Nature Methods paper, and I published an overview and critique in 2019.